1. Field of the Invention
This invention relates to a plastic molded type semiconductor device and a method of manufacturing it.
2. Description of the Related Art
With rapid advances in ICs and memory cards, there has recently been a demand for thin ones as plastic molded type semiconductor devices installed in the cards. As methods of realizing the thin-type semiconductor devices, a vast number of proposals have been made. One example is shown in FIGS. 25(a) and 25(b).
In FIGS. 25(a) and 25(b), reference numeral 1 indicates a plastic molded type semiconductor device and reference numeral 2 indicates a semiconductor element. The semiconductor element 2 has one surface to which a chip support 4 is bonded and fixed by an insulating adhesive tape 3. Further, leads 6 are electrically connected to the semiconductor element 2 through gold wires 5 connected to both sides of the chip support 4. The plastic molded type semiconductor device 1 is formed by sealing the semiconductor element 2 with a mold resin 7 so that the upper surface of the chip support 4 and the bottom face of the semiconductor element 2 are exposed.
According to such a structure, since the bottom face of the semiconductor element 2 is not covered with the mold resin 7 in particular, the semiconductor device can be made thin correspondingly.
However, if consideration is given to an area for the implementation of the semiconductor device 1 on a printed board even though the thickness of the plastic molded type semiconductor device 1 can be thinned, an area much wider than the size of the semiconductor element 2 is required as its implementation area because the leads 6 extend long toward the outside of the mold resin 7. Thus, if the implementation of the plastic molded type semiconductor device 1 on the printed board is taken into consideration, then problems to be improved still remain to realize denser packing.